Fix vanilla issue: Production panel shows incorrect completion time for wonders if there are multiple bonuses

[bollbas]

When a player has 2 bonuses to wonder production, Production panel uses only one of them to calculate turns to complete values. See more on civfanatics.

[chaorace]

Is this an issue in vanilla as well?

[bollbas]

Yes, I checked it

[JHCD]

Is it an display error? Or does Vanilla not accept multiple bonuses?

[bollbas]

Yes, it's only a display error. In fact we build a wonder faster that it is shown in production panel when we have 2 bonuses.

[chaorace]

Reframing this as an enhancement since the issue comes from the game itself